A Northwoods Almanac for 3/31 – 4/13,
2017
Sightings
3/13: The bald
eagle pair that nests across the Manitowish River from our house began
incubating eggs today. The activity around the nest now involves an eagle
flying in and settling down into the nest, while another one emerges from lower
in the nest and flies off. Bald eagles share the incubation of their eggs, so
this trading of tasks is regular throughout the day. Incubation typically lasts
around 30 days, so we expect to see the activity around the nest change again
around April 13 when they will then be tasked with feeding the chick or chicks.
This is, by the way, an early date for nesting – the average date is closer to
April 1. Bob Kovar in Manitowish Waters also reported that the eagle pair
nesting on his property began incubating the same day.
3/17: Our FOY
(First-Of-Year) red-winged blackbirds returned to our feeders in Manitowish, as
did an American tree sparrow.
3/23: Our FOY
white-throated sparrows returned to Manitowish.
3/24: Nancy
Burns spotted the FOY hooded mergansers on the Manitowish River.
3/25: Sharon
Lintereur in Lake Tomahawk saw movement in their owl nesting box, and it turns
out that for the second consecutive year, a pair of barred owls are nesting
there. Barred owls nest most often in deciduous trees, primarily in cavities
formed by disease, broken branches, or cavities in the top of broken trees
(snags). However, they will use open stick nests built by hawks, crows, ravens,
or squirrels, too. They also readily take to nest boxes, as is the case at the
Lintereur home. Incubation is done solely by the female and is usually about a
month, with an average clutch size of 2 to 3 eggs. If more than 3 eggs are
laid, each on successive days, the youngest of the brood often is underweight
and weak, and may be eaten by its nestmates.
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| photo by Sharon Lintereur |
3/25: Mary and I
spotted our FOY common goldeneyes, red-breasted mergansers, and common
mergansers in Marquette, MI, on Lake Superior.
3/27: Our FOY
common grackles appeared at our feeders in Manitowish.
On the Horizon
Numerous species of birds have
migrated into southern Wisconsin and most are poised to continue their flights
into the Northwoods as the weather warms. Keeping records on when various
species return is all part of phenology, or the study of the orderly timing and
progression of natural events. Others define it as the study of biological
cycles and seasonal rhythms. It’s nature’s calendar. I encourage you to keep a
calendar of your first sightings, from ice-off on your lake, to the first birds
and flowers, to various temperature and rainfall recordings. Relying on our
memories, at least for those of us without photographic memories, is a sure way
to ruin otherwise. Then pass on your records to the next person who will own
your home, so they know what to look for and when.
Five Drummers Drumming
Woodpeckers are beginning to drum
regularly on trees around our home, the males now establishing territories and
beginning to woo a mate. If you pay attention to the duration, speed, and volume
of the drumming, you can identify the species by the drum pattern. We only have
five common woodpeckers in our area – pileated, hairy, downy, northern flicker,
and yellow-bellied sapsucker – so it’s not too daunting. You may also hear
red-bellied woodpeckers which continue to slowly move north into the Lakeland
region, as well as red-headed woodpeckers which have become less common. And if
you are particularly blessed, you could hear a black-backed woodpecker. But we
are at the southern-most edge of their range, and they’re rare.
The drumming for territories and
mates is different from that of the arrhythmic tapping heard from woodpeckers
as they excavate nests and search for insects. The drumming from yellow-bellied
sapsuckers is an easy one to start with because it starts strong with several
relatively fast taps, then slows down, and finally fades out at the end. It can
be very irregular, often changing in successive drumrolls – you can think of it
as a Morse code: Tap-Tap-Tap…tap-tap-tap . . . tap . . . tap . . . tap.
The pileated is the power drummer of
the crew, pounding out a crescendo that is deep and resonant, lasting for three
seconds or more. Both genders drum, but the females less frequently. Famed
ornithologist George Sutton described the sound as a repeated sequence of “an
introductory, rapidly given ; then a pause, followed by three distinct blows;
another pause; and two concluding blows.” It’s the volume that gives this one
away without a doubt, and you can literally hear the hollowness of the tree.
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| pileated chicks in nesting cavity |
Things get a little dicier now in
identifying the drumming patterns. The drumming of northern flickers has been
described as “a miniature pneumatic drill,” produced by even, rapid blows. The
drum roll only averages a little more than a second long, but contains 25 beats
in a roll. Like many woodpeckers, flickers will often drum on a metal surface.
One flicker in Wyoming beat on the cowling of an abandoned farm tractor and
could be heard almost a half-mile away.
The hairy woodpecker drums at a
relatively steady rate, but more rapidly and with longer pauses than the downy
woodpecker. Its drumroll lasts about a second and has 26 beats – it goes by so
fast that you can’t pick out the individual taps – whereas a downy’s drumroll
lasts three-quarters of a second and averages 13 beats. Here you can just pick
out each tap.
The
downy also loves to drum more, offering 9 to 16 drumrolls a minute versus the
less enthusiastic hairy which only drums 4 to 9 times a minute.
Both
sexes drum in all these species for a variety of reasons:
1. To
defend a territory
2. As
part of a courtship
3. To
solicit copulation
4. To
summon a mate from distance away
5. To
communicate their location to a mate or in response to a nest intruder
6. Or
for reasons no one will ever know
Drumming does occur year-round in
woodpeckers, but it’s much more intensive in spring. While species
identification from drumming can be done with practice, if I had a nickel for
every misidentification I’ve made of birds, I’d be a wealthy man.
Saw-whet Owls Calling
I’ve yet to hear a saw-whet owl “singing,”
but now is the time to go out after dark and listen for their monotonous
tooting. While saw-whets produce a series of different calls, the one most
often heard is the “advertising call,”
which is an endless loop of whistled “toots” on a constant pitch. The call
comes at a rate of about two per second and sounds, and when researchers say
it’s monotonous, they really mean monotonous – the song can literally go on for
an hour or more.
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| saw-whet owl range map |
Celestial Events
Jupiter will be at its closest to
the Earth on 4/7 and brighter than at any other time this year, and is also
visible all night. You should be able to see Jupiter’s four moons with a good
pair of binoculars. If you can’t, this is a good excuse to buy that spotting
scope you’ve always wanted – see www.eagleoptics.com. The moons are often called Galilean
moons for Galileo who discovered them in 1610.
Galileo was employed by Cosimo de’
Medici, the Grand Duke of Tuscany. In seeking further patronage from this
wealthy family, he used the discovery of the moons to name them the “Medician
Stars” after the Medici Clan. He wrote a dedication letter to the Duke in which
he said, “Scarcely have the immortal graces of your soul begun to shine forth
on earth than bright stars offer themselves in the heaven which like tongues
will speak of and celebrate your most excellent virtues for all time. Behold,
therefore, four stars reserved for your illustrious name . . .” It occurs to me
this practice continues in our time, but is used to gain money by naming
stadiums after corporations, not moons after Dukes.
On
4/10, look for Jupiter in the southeast just two degrees below the nearly full
moon. Full moon occurs the next day, 4/11.
For
planet viewing in April, look after dusk for Mars very low in the western
twilight – it’s lost by late-month. Jupiter is very bright in the southeast.
Before dawn, look for Venus very low in the eastern twilight and climbing. Look
also for Saturn in the south (Saturn rises after 1 a.m. in the ESE if you are
wandering around at that hour). Saturn’s rings are tilted at nearly 27 degrees
from edge-on.
April 12 marks the anniversary of
the first human in space – Yuri Gagarin in 1961 from Russia – when the race for
space really heated up.
Thought for the Week
“Wisdom
grows as a river grows, from the accumulation of many small things.” Kathleen
Dean Moore
Please share
your outdoor sightings and thoughts: call 715-476-2828, e-mail at manitowish@centurytel.net, snail-mail at 4245N Hwy. 47, Mercer,
WI
